As I mentioned in a previous post about my attendance to a powerlifting seminar a few weeks ago, I finally bit the bullet and started experimenting with Sumo DL's. Now I'm doing two sets of five reps with the working weight I've previously used for an AMRAP set (conventional), which I increase 5 kg per week, and we'll see where it takes me.
What I noticed last week (working w 155 kg) is that I was first straightening the legs (while keeping the back angle relative to the floor constant) and only then raising the bar, which I did in two noticeably distinct phases: a first one (until the hands touched the thighs) that required mainly glutes and erectors contracting, which I'll call Stage III, and a second one (to lockout) requiring more upper back, Stage IV. Something like this:
Not very nice, and regardless of how much I tried to engage the lats and keep the bar close to shins (& then knees) I felt it tended to hang too far in front, so stage III in the drawing was a pretty ugly, draining thing.
Yesterday (DL day again!) I focused on keeping the back more upright since the get go, trying to make Stage III unnecessary. That requires to put the hip a tad lower, puff up the chest so the shoulders are also a tad more behind the bar and start moving up by straightening the legs (pure quads) while thinking in pulling back, so the bar brushes the knee and touches the thigh at the exact moment in which the upper back is retracting the shoulders to lockout.
Being tired as hell and with the hands utterly shredded I found it quite challenging overall, and if the bar (or rather, the hands holding the bar) makes contact with the leg one inch higher or lower than where they have to be at the end that makes locking out the knees almost impossible. However, I think it is the way to go training-wise, as it definitely puts a lot of pressure on quads, hammies and glutes (and not so much on erectors, which is great as they are thrashed enough by previous conventional sets), and of course on flexors.
However, still have to investigate more what kind of proportions (between legs, torso and arms, and also between femur, tibia and fibula) make sumo deadlifts more advisable to see if I have to progress them into higher intensity ranges. At least, if I finally decide to do so, the foundations are more solidly layed out than a month ago